Australasian Plant Pathology最新文献

{"title":"Development of a qPCR assay to detect Diplodia seriata on chipped apple wood","authors":"Vernon Jacobs,&nbsp;Francois Halleen Elodie Stempien,&nbsp;Lizel Mostert","doi":"10.1007/s13313-024-00991-7","DOIUrl":"10.1007/s13313-024-00991-7","url":null,"abstract":"<div><p>In the deciduous fruit industry, orchards are often excavated and trees chipped. The organic material is then used as mulch for soil conservation, a practice that form part of sustainable agricultural. The presence and possible transmission of plant pathogens are not considered when trees are removed, chipped and used for mulch. Young apple trees can develop cankers due to <i>Diplodia seriata</i> of which the inoculum source might come from fruiting structures present on apple wood mulch. Therefore, the presence of <i>D. seriata</i>, on chipped apple tree wood pieces used for mulch in younger orchards was investigated. To be able to detect <i>D. seriata</i>, qPCR primers were designed from a previously identified unique sequence characterised amplified region (SCAR). The qPCR primers were specific for <i>D. seriata</i> (Cq ≤ 35 and Tm = 85<span>(:pm:)</span>0.17 °C) when compared with DNA from nineteen other fungal taxa associated with canker or wood rot of apple trees tested, excluding <i>Botryosphaeria dothidea</i> (Cq = 38 and Tm = 85.25 °C). The qPCR assay was sensitive and had a limit of quantification of 2859 fg/µl and limit of detection of 571 fg/µl. Wood chips were collected at two time periods (from heaps and 6 months after it was spread in tree rows) in three apple orchards in the Western Cape of South Africa. DNA was extracted from water-washes of 120 wood piece samples and <i>D</i>. <i>seriata</i> was detected from 101 of these samples. This study showed that the newly developed primers was able to successfully detect <i>D. seriata</i> from mulched apple wood. The presence of <i>D. seriata</i> on apple tree wood chips indicates that there is a risk involved in using wood chips made from old apple trees.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 5","pages":"413 - 418"},"PeriodicalIF":0.9,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13313-024-00991-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of Calonectria variabilis isolated from Anacardium occidentale trees exhibiting leaf blight symptoms","authors":"Luis A. Ramírez-Camejo,&nbsp;Iliana Quintero,&nbsp;Marjorie Cedeño–Sanchez,&nbsp;Luis C. Mejía","doi":"10.1007/s13313-024-00985-5","DOIUrl":"10.1007/s13313-024-00985-5","url":null,"abstract":"<div><p><i>Anacardium occidentale</i> is the tree source of cashew nuts, a commodity with increased demand globally and threatened by several diseases. Here we report on the occurrence of a disease that has severely affected production of cashew nuts in Panama and that can be of regional importance. Our first observation of this disease was in 2013, in the locality of Gamboa (Colon, Panama). Blight symptoms of the disease starts with foliar lesions characterized by initial necrotic points surrounded by yellow discoloration or chlorotic zones. These lesions progressively expand, transforming into larger, brown patches with rounded to irregular shapes. Lesions can coalesce and cover entire leaves causing them to drop and produce defoliation of entire branches or trees that become unproductive. Trees with similar symptoms were later observed in several provinces in Panama indicating that the disease was widespread in the country. We obtained consistent isolation of the same fungus from lesions on <i>A. occidentale</i> from multiple localities and pathogenicity tests were conducted on detached leaves as well as on healthy leaves on an adult tree. Morphological and phylogenetic analyses of the isolated fungus showed that the causal agent was <i>Calonectria variabilis</i>, a fungus previously reported to occur on <i>Schefflera morototoni</i>, <i>Theobroma grandiflora</i>, and <i>Eucalyptus</i>. This is the first time that <i>C. variabilis</i> is reported as a pathogen of <i>A. occidentale</i> and the first record of this species for Panama.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 5","pages":"375 - 383"},"PeriodicalIF":0.9,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative gene expression of OsSWEETs from various rice genotypes during the development of bacterial blight as induced by the most virulent Race 4 of Xanthomonas oryzae pv. oryzae","authors":"E R Rashmi,&nbsp;Kalyan K. Mondal,&nbsp;Thungri Ghoshal,&nbsp;M Amrutha Lakshmi","doi":"10.1007/s13313-024-00990-8","DOIUrl":"10.1007/s13313-024-00990-8","url":null,"abstract":"<div><p>Sugars are caloric carbohydrate compound found in nature, such as fruits and vegetables, and are required by all organisms. During the phloem loading process, SWEET efflux sucrose from phloem parenchyma cells and then transports it to the sieve element-companion cell complex (SE/CC) via active proton-coupled sucrose transporters (SUTs). There are 21 SWEETs identified in rice that play important roles in sugar efflux, signal transduction, plant growth and development, and biotic and abiotic stress tolerance. TALE proteins are pathogen-produced effectors that interact with host susceptibility genes and induce OsSWEET proteins. In this study, genetic variations in the promoter region of <i>OsSWEET11</i>, <i>OsSWEET13</i> and <i>OsSWEET14</i> are examined in 20 genotypes grown in India. Further sequence analysis of three genotypes having extreme response (resistance and susceptibility) to bacterial blight revealed that the promoter of the resistant genotype Pusa basmati 1692 is more closely clustered with the <i>xa13</i>, <i>xa25</i> resistance genes than compared to susceptible genotype Pusa basmati 1. Relative gene expression studies showed that upon <i>Xoo</i> inoculation, the fold expression of clade III <i>OsSWEET</i> genes, namely <i>OsSWEET11, OsSWEET13, OsSWEET14</i> and <i>OsSWEET15</i> increases in cultivars IR24, Pusa Basmati1 and Improved Pusa Basmati1. Intriguingly, after <i>Xoo</i> challenge inoculation, <i>OsSWEET15</i> expression was found to be increased along with other major <i>OsSWEET</i> genes, implying that it could be a novel target for a bacterial blight pathogen.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 5","pages":"401 - 412"},"PeriodicalIF":0.9,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Infected nursery stock and poor silvicultural practices contribute to development of Ceratocystis manginecans wilt and canker disease in Eucalyptus pellita","authors":"H. Indrayadi,&nbsp;Morag Glen,&nbsp;Y. R. Kurniawan,&nbsp; Fahrizawati,&nbsp;C. Beadle,&nbsp;D. Ratkowsky,&nbsp;B. Tjahjono,&nbsp;C. Mohammed","doi":"10.1007/s13313-024-00989-1","DOIUrl":"10.1007/s13313-024-00989-1","url":null,"abstract":"<div><p>In Indonesia and Malaysia, <i>Eucalyptus pellita</i> has replaced large areas of <i>Acacia mangium</i> plantations as the latter species is highly susceptible to <i>C. manginecans.</i> This strategy may not be effective in the long term as <i>E. pellita</i> is also susceptible to Ceratocystis wilt and canker disease though it has higher tolerance than <i>A. mangium.</i> Furthermore, the pathogen has the capacity to evolve and adapt to new hosts. To highlight the need for careful sanitation in nurseries and the potential impact of wounding during silvicultural operations, two experiments were conducted to (i) demonstrate the ability of cryptic <i>Ceratocystis</i> infections in nursery plants to develop into Ceratocystis wilt and canker disease after planting out and (ii) assess the risk of Ceratocystis infection and disease development from different wound types. In the nursery, three-month-old mini-cuttings of seven <i>E. pellita</i> clones were artificially wounded and inoculated with two isolates of <i>Ceratocystis manginecans</i> near the base of the stem. The disease incidence and lesion length were measured one month later, just prior to planting out. After four months of growth in the plantation, the trees were harvested and stems sliced longitudinally to measure the length of xylem discolouration. Six of 36 ramets of susceptible clones died and the length of xylem discolouration was significantly greater in susceptible clones than in tolerant clones. The second experiment was based on inoculation of 12-month-old plantation-grown trees of one clone of <i>E. pellita</i> with one isolate of <i>C. manginecans</i> using six different wounding methods. The inoculated wounds on the trees all produced xylem discolouration, except for those that only penetrated the outer bark. Disease incidence was greater at stem heights of 30 to 90 cm than on the basal stem or branch stub. The experiment emphasised the importance of minimising the risk of <i>C. manginecans</i> infection following wounding in the nursery and in the field as the discolouration is an indication of xylem blockage that can lead to tree mortality.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 5","pages":"391 - 399"},"PeriodicalIF":0.9,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13313-024-00989-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization and functional validation of a genomic region involved in resistance to rust race II in Coffea arabica","authors":"Caroline Ariyoshi,&nbsp;Suzana Tiemi Ivamoto-Suzuki,&nbsp;Viviane Yumi Baba,&nbsp;Masako Toma-Braghini,&nbsp;Gustavo Hiroshi Sera,&nbsp;Adrian Powell,&nbsp;Sandra Maria Bellodi Cação,&nbsp;Eveline Teixeira Caixeta,&nbsp;Luiz Filipe Protasio Pereira","doi":"10.1007/s13313-024-00988-2","DOIUrl":"10.1007/s13313-024-00988-2","url":null,"abstract":"<div><p>Coffee leaf rust (CLR) is one of the most economically important diseases affecting <i>Coffea arabica</i> production, having a significant economic impact. Among the main goals of coffee breeding programs is the development of cultivars resistant to this disease. A source of resistance genes is Híbrido de Timor (HdT), a spontaneous hybrid originated from the cross between <i>C. arabica</i> and <i>C. canephora</i>. Previously, in a transcriptome study, the <i>Ca TDF77 NBS-LRR</i> gene from HdT involved in resistance to CLR was identified. Hence, our aim was to characterize the genomic region surrounding the <i>Ca TDF77 NBS-LRR</i> gene in <i>Coffea</i> spp. Furthermore, we aimed to analyze the transcriptional profile of this gene, in the <i>C. arabica</i> cultivar IAPAR 59, which is originated from HdT introgression and is resistant to CLR race II. The outcome delineated the gene’s localization on chromosome 11 (canephora subgenome) of <i>C. arabica</i>, spotlighting intragenic polymorphisms between HdT and Arabica coffee susceptible to CLR race II. The genomic region surrounding the gene in <i>Coffea</i> spp. revealed a tandem structure and transposable elements. Notably, within IAPAR 59, the gene exhibited significant upregulation at 24 and 72 h post CLR infection, contrasting starkly with the susceptible genotype. This observation validates its role in fortifying the defense mechanism of this particular cultivar. This study enriches our understanding of the evolutionary dynamics of <i>Coffea</i> spp. genomes and also provides genomic resources instrumental in devising biotechnological strategies for resistance to CLR.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 4","pages":"363 - 373"},"PeriodicalIF":0.9,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elucidating the role of nitrogen and silicon regimes in rice blast management and yield performance of Mushk Budji variety under field conditions","authors":"Zakir Amin,&nbsp;F. A. Mohiddin,&nbsp;Ali Anwar,&nbsp;Asif. B. Shikari,&nbsp;Tauseef A. Bhat,&nbsp;Fehim Jeelani Wani,&nbsp;T. A. Raja,&nbsp;Zahoor Ahmad Baba,&nbsp;Najeebul Rehman Sofi,&nbsp;Shugufta Parveen,&nbsp;Heena Altaf","doi":"10.1007/s13313-024-00986-4","DOIUrl":"10.1007/s13313-024-00986-4","url":null,"abstract":"<div><p>This study investigated the interactive effects of nitrogen and silicon fertilization on disease incidence, severity, grain yield, and straw yield in susceptible rice variety under rice blast disease pressure across two consecutive years. The results revealed significant variations in disease parameters across different nutrient combinations. The study involved four levels each of nitrogen (N₀: 0 Kg/ha; N₁:50 Kg/ha; N₂: 100 Kg/ha and N₃: 150 Kg/ha) and silicon (Si₀: 0 Kg/ha; Si₁: 60 Kg/ha; Si₃: 90 Kg/ha and Si₃: 120 Kg/ha). The treatments with lower to moderate nitrogen levels coupled with higher silicon rates exhibited the lowest disease incidence and severity, highlighting their synergistic effect in enhancing disease resistance. Conversely, high nitrogen levels with low or no silicon supplementation displayed the highest disease susceptibility, indicating that excessive nitrogen without adequate silicon can exacerbate vulnerability. Notably, increasing silicon levels led to decreasing disease incidence and severity, while the opposite trend was observed for nitrogen, underscoring silicon’s pivotal role in mitigating disease impact. Regarding yield parameters, the highest silicon rate (120 kg/ha) consistently resulted in superior grain yields, particularly when combined with moderate nitrogen levels (100 Kg/ha). The positive effect of silicon on grain yield was more pronounced at lower nitrogen levels, suggesting its potential to compensate for nitrogen deficiency. Moreover, the highest silicon level consistently exhibited superior straw yields across nitrogen levels. However, moderate nutrient levels occasionally outperformed the highest levels, implying an optimum range for maximizing straw yield while avoiding yield penalties associated with excessive application.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 4","pages":"353 - 362"},"PeriodicalIF":0.9,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Response to the detection of Fusarium dieback associated with ambrosia beetles on Acer negundo in New South Wales","authors":"Sophia Callaghan,&nbsp;Angus J. Carnegie,&nbsp;Peter Gillespie,&nbsp;Shannon Mulholland,&nbsp;Matthew Nagel,&nbsp;David Sargeant,&nbsp;Andrew Daly,&nbsp;Ossie Wildman","doi":"10.1007/s13313-024-00984-6","DOIUrl":"10.1007/s13313-024-00984-6","url":null,"abstract":"<div><p>Symptoms consistent with polyphagous shot hole borer (<i>Euwallacea fornicatus</i>) and <i>Fusarium</i> dieback (<i>Fusarium euwallaceae</i>), recognised as high priority environmental pests for Australia, were observed on a single box elder (<i>Acer negundo)</i> tree in Sydney, New South Wales, in March 2022 during routine forest biosecurity surveillance. Delimiting surveys were undertaken around the Sydney basin, extending radially from the original box elder, resulting in the detection of a further three box elder and one tuckeroo (<i>Cupaniopsis anacardioides</i>) with suspicious symptoms. Samples were taken from the five trees and associated beetles diagnosed using morphological and molecular methods. Associated <i>Fusarium</i>-like fungi were identified according to phylogenetic inference using regions of the internal transcribed spacer, as well as the translation elongation factor 1-α and RNA polymerase II genes. The tea shot hole borer, <i>Euwallacea perbrevis</i>, was identified along with its known fungal mutualist, <i>Fusarium obliquiseptatum</i>. This pair have been reported in Queensland on avocado (<i>Persea americana</i>) and tuckeroo, and there are unpublished records of <i>E. perbrevis</i> from northern NSW, but this is the first report of both species occurring simultaneously in NSW. The biosecurity response following the initial detection, including the establishment of an Incident Management Team, surveillance, diagnostics, and stakeholder engagement, is discussed. This paper highlights the importance of surveillance for early detection of invasive pests and biosecurity systems and processes for enabling a timely response.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 4","pages":"345 - 352"},"PeriodicalIF":0.9,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13313-024-00984-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of plasmid and its role in phytopathogenic bacteria Xanthomonas citri pv. viticola strains","authors":"Sneha Bhosale,&nbsp;Sujoy Saha,&nbsp;Nayana Patil","doi":"10.1007/s13313-024-00982-8","DOIUrl":"10.1007/s13313-024-00982-8","url":null,"abstract":"<div><p>The most significant bacterial disease infecting grape is bacterial leaf spot (BLS), caused by <i>Xanthomonas citri</i> pv. <i>viticola</i> (<i>Xcv</i>) strain. In the field, BLS severity depends on host genotype, pathogen pressure and environmental conditions. Plasmids, the extra chromosomal DNA components of phytopathogenic bacteria, play a crucial role in disease development as well as in the diverse evolution of the pathogen. Genome diversity and distribution of genes responsible for various factors present on plasmid in the pathogen are not well understood. The current research aimed to investigate various plasmid-borne traits in <i>Xcv</i> strains collected from twenty-three different locations. Four different curing agents viz. ethidium bromide (EtBr), acridine orange (AO), sodium dodecyl sulphate (SDS) and elevated heat were used to cure the plasmid. The findings revealed uniform plasmid size of approximately 23 kb among all isolates of India. The study also reveals the effect of plasmid curing on various traits, including morphology, pathogenicity, exopolysaccharide production, and antibiotic sensitivity. Exopolysaccharide production and pathogenicity were significantly reduced in the cured isolates. Cured <i>Xcv</i> isolates also exhibited significant variation in tested traits, displaying phenotypic differences in color, size, shape, elevation, appearance and margin. The study further emphasized the crucial role of plasmids as carriers for genetic exchange among plant pathogenic bacteria, contributing to bacterial adaptation to the environment. Additionally, the research highlighted the presence of antibiotic resistance traits on the plasmids and the importance of plasmid-mediated mechanisms in bacterial adaptation.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 4","pages":"325 - 334"},"PeriodicalIF":0.9,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of sources of resistance and comparative metabolomic profiling of resistant and susceptible chilli germplasm to Meloidogyne incognita Race 1","authors":"Prasanna Holajjer,&nbsp;T. P. Ahammed Shabeer,&nbsp;M. K. Mahatma,&nbsp;Z. Khan,&nbsp;S. R. Pandravada,&nbsp;N. Sivaraj,&nbsp;Anitha Kodaru,&nbsp;Anita Pardeshi","doi":"10.1007/s13313-024-00981-9","DOIUrl":"10.1007/s13313-024-00981-9","url":null,"abstract":"<div><p>Root-knot nematode, <i>Meloidogyne incognita</i> Kofoid and White, 1919 is a major endoparasite that causes significant economic losses in several Solanaceous crops worldwide, including chilli (<i>Capsicum annuum</i>). In the present study, 66 accessions were screened for sources of resistance to <i>M. incognita</i> Race 1. The accessions EC399535 and EC402105 showed less than 10 number of galls and egg mass per root system [RKI:2 (1–10 galls or egg mass/ root system)] and identified as resistant accessions against <i>M. incognita</i>. Further, metabolic profiling analysis in the roots of resistant and susceptible (EC378632 and Arka Lohit) accessions exposed to <i>M. incognita</i> was carried out using gas chromatography-mass spectrometry (GC-MS). Non-targeted metabolic analysis detected 116 metabolites, which were further subjected to partial least squares-discriminant analysis (PLS-DA) with variable importance in projection (VIP) score to measure accumulation pattern in resistant and susceptible genotypes. VIP score revealed that 14 metabolites showed higher accumulation (&gt; 1.5 VIP score) in resistant germplasm compared to susceptible germplasm. Specific metabolites viz., phytosterols, delta-tocopherol and squalene showed &gt; 2.0 VIP score. Heatmap analysis differentiated metabolite abundance in each germplasm under <i>M. incognita</i>-infected and non-infected conditions. Dendrogram clustering analysis of metabolites data clearly separated resistant and susceptible accessions. The most significant metabolic pathways activated in <i>M. incognita</i>-resistance were phenylalanine metabolism (0.23529 impact), and sesquiterpenoid and triterpenoid biosynthesis (0.21622 impact) and alanine, aspartate and glutamate metabolism (0.19784 impact). This study provides valuable insights into compounds involved in defense activities against <i>M. incognita</i>. However, more research on the nematostatic or nematicidal activities of these metabolites including chemical inhibition or gene silencing of metabolites in plants is required for understanding the resistance mechanism and utilizing these metabolites as a biomarkers in resistance breeding programme.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 4","pages":"313 - 324"},"PeriodicalIF":0.9,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141921073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling defense strategies: gene expression dynamics in blast-resistant vs. susceptible aromatic rice landraces","authors":"U. Keerthana,&nbsp;A. K. Senapati,&nbsp;Manas K. Bag,&nbsp;S. R. Prabhukarthikeyan,&nbsp;Shraddha B. Sawant,&nbsp;M. K. Mishra,&nbsp;S. D. Mohapatra","doi":"10.1007/s13313-024-00983-7","DOIUrl":"10.1007/s13313-024-00983-7","url":null,"abstract":"<div><p>In this study, efforts were made to understand the defence responses in resistant and susceptible aromatic landraces against the rice leaf blast pathogen, <i>Magnaporthe oryzae</i>. Four resistant genotypes (Benugopal, Manas, Karpurkali, and Kalazeera) and two susceptible genotypes (Kalikati 2 and Kalikati 1) underwent biochemical analysis in relation to blast disease. The results of the biochemical analysis revealed increased enzyme activity levels, namely peroxidase, phenylalanine ammonia-lyase, polyphenol oxidase, superoxide dismutase, and catalase, in the resistant genotypes (Benugopal (AC44184) and Karpurkali (AC44155)) in comparison to the susceptible ones [Kalikati 2 (AC44236) and Kalikati 1 (AC44156)]. The same trend has been seen in the assays for β-1,3-glucanase and total phenols. RT-qPCR evaluation has been performed to establish the expression levels of PO, PAL, PPO, SOD, and CAT in the four resistant genotypes and the two susceptible ones after inoculation with <i>M. oryzae</i> (RLB 06) at various time intervals. Noteworthy variations in defence gene expression were noted among the genotypes. The expression of defence genes was upregulated in the resistant genotypes [Benugopal (AC44184) and Karpurkali (AC44155)] compared to their susceptible ones. Gene expression studies result indicated that the relative defence genes expression levels related to the spectrophotometric data.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"53 4","pages":"335 - 343"},"PeriodicalIF":0.9,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141920301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}